This line shows that your print job was sent with the option "number-up=2", which means 2 pages per sheet, and this was correctly executed.

What you need is to turn off the "number-up=2" option. Firdt look in system-config-printer, right-click printer icon, "Properties", "Job Options". Look whether there is an option for 2 pages per sheet set. Set it to 1 page per sheet.

Check also whether you have a ~/.cups/lpoptions file. Look into the file and if there is "number-up=2" in it somewhere, remove the "number-up=2".